Cybister sugillatus Erichson, 1834

Jiang, Zhuo-Yin, Zhao, Shuang, Mai, Zu-Qi, Jia, Feng-Long & Hendrich, Lars, 2023, Review of the genus Cybister in China, with description of a new species from Guangdong (Coleoptera: Dytiscidae), Acta Entomologica Musei Nationalis Pragae 63 (1), pp. 75-102 : 97

Cybister sugillatus Erichson, 1834

( Figs 17A–E ; 18D–E, H ; 19F ; 22B )

Cybister sugillatus Erichson, 1834: 227 (orig.descr.); RḖGIMBART (1899): 355 (Xizang); ZIMMERMANN (1919): 77 (Taiwan); KANO (1931): 176 (Taiwan); FENG (1932): 36 (Beijing, Fujian: Fuzhou and Xiamen, Guangdong, Hainan, Hubei: Wuchang, Jiangxi, Sichuan, Xizang, Zhejiang); FALKENSTRÖM (1936): 238 (Sichuan); ZHAO (1981): 110 (Fujian); ZENG (1989): 92 (Beijing, Fujian, Guangdong, Hainan, Hubei, Jiangxi, Sichuan, Xizang, Zhejiang); MORI & KITAYAMA (1993): 142 (Taiwan).

Cybister bisignatus Aubé, 1838: 88 (orig. descr.), synonymy by SHARP (1882: 991).

Cybister notasicus Aubé, 1838: 90 (orig. descr.), synonymy by SHARP (1882: 717).

Cybister olivaceus Boheman, 1858: 21 (orig. descr.), synonymy by SHARP (1882: 717).

Material examined. CHINA: GUANGDONG: 8JJ 7♀♀, Guangzhou, 14.xi.1964, T. X. Peng purchased from market ( SYSU); 1 ♀, Ruyuan County, Tianjingshan Mt., 8.viii.1980, Q. X. Zhang leg. ( SYSU); 1 J, Fengkai County, Heishiding, 10.iv.1985, W. Wu leg. ( SYSU); 1 J, Fengkai County, Heishiding, 14.vii.1999, Y. C. Wang leg. ( SYSU); 1 ♀, Fengkai County, Heishiding, 12.vii.2000, Y. L. Feng leg. ( SYSU); 2 JJ 2 ♀♀, Gaoming District, Yangmei Township, 20–27.iv.2006, D. P. Wu, N. Yu, Q. S. Liu & Y. Y. Niu leg. ( SYSU); 1 J, Zhuhai, back mountain of Sun Yat-Sen University, 5.–8.vii.2011, F. L. Jia leg. ( SYSU). GUANGXI: 1 ♀, Rong’an County, Dajiang-Yayao, 28.iv.1959 ( SYSU); 2 JJ 1 ♀, Nanning, iii.2001, L. Hojný leg. ( NMPC); 1 J, Jingxi, Bangliang Nature Reserve, 1.viii.2010, J. H. Huang leg. ( SYSU). HAINAN: 1J, Cheung-kon-ts’uen, Ka-luk-kong (18ml. E.of Nam-fung), Kiung-shan Dist., 29.–31.iii.1935, F. K. To leg. ( SYSU); 1 ♀, Lingshui County, 1.i.1964, T. X. Peng leg. ( SYSU); 1 ♀, Jiangfengling, the third partition, 24.xi.1981, J. P. Lu leg. ( SYSU); 1 J, Jiangfengling, Heiling, 10.vii.1982, L. Z. Hua leg. ( SYSU). HONG KONG: 1 J, Hong Kong, 1934 ( SYSU). YUNNAN: 1 J 1 ♀, Chengjiang County, 30.iv.1932, Z. L. Pu leg. ( SYSU).

Diagnosis. TL 18–23 mm, elongate, oblong-oval ( Fig. 17A ). Head, pronotum and elytra dark green to black, lateral part of pronotum reddish-brown, apex of elytra with reddish-brown spots. Ventral surface black; abdominal ventrites III–IV with a yellow spot on each side ( Fig. 17B ). Dorsal surface smooth. Prosternal process lanceolate, with distinct lateral bead, surface flat, apex pointed; lateral parts of metaventrite tongue-shaped, slender, not reaching lateral margins; metacoxal lines distinct, well impressed, nearly parallel medially, divergent anteriorly, along metacoxal lines with a row of punctures. Forelegs reddish-brown, midlegs and hindlegs reddish-brown to black; protarsomeres 1–3 of male broadly expanded into a palette, with four rows of adhesive setae on their ventral side; male with a single metatarsal claw; female with two metatarsal claws, posterior claw small and sinuate. Medi- an lobe of aedeagus ʻCʼ- shaped in lateral view, strongly curved, broadest at middle, strongly narrowing in apical fifth, apex rounded ( Fig. 17C ); broad medially in ventral view, apical fifth slender like a tubular spine, apex rounded ( Fig. 17D ). Parameres moderately broad, strap-like apically ( Fig. 17E ).

Habitat. This species inhabits not only ponds, wetlands, abandoned paddy fields and ditches of paddy fields with aquatic plants, but also eutrophic waters near grazing land

( MORI & KITAYAMA 1993). Specimens from Shenzhen (Guangdong) were found in in a lowland marsh ( Figs 18D–E ) and specimens from Lvchun County (Yunnan) were found in terraced fields ( Fig. 18H ).

Distribution. China (Beijing, Fujian, Guangdong, Guangxi, Hainan, Hebei, Hong Kong, Hubei, Jiangxi, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang) ( Fig. 22B ), Afghanistan, Bhutan, India, Indonesia, Japan, Laos, Malaysia, Myanmar, Nepal, Pakistan, Philippines, Singapore, Sri Lanka (RḖGIMBART 1899; ZIMMERMANN 1920; FENG 1932, 1933b; GSCHWENDTNER 1938; VAZIRANI 1969; ZAITZEV 1972; ZENG 1989; MORI & KITAYAMA 1993; NILSSON 1995; HENDRICH et al. 2004; GHOSH & NILSSON 2012; HENDRICH & BRANCUCCI 2013; NILSSON & HÁJEK 2022b). First record from Guangxi and Yunnan.

Figures

Fig. 17. Cybister sugillatus Erichson, 1834 (J, Shenzhen, Guangdong). A – habitus in dorsal view; B – habitus in ventral view; C – median lobe of aedeagus in lateral view; D – median lobe of aedeagus in ventral view; E – paramere. Scale bars: 5.0 mm (A, B), 1.0 mm (C–E).

Fig. 18. Habitats of Cybister in China. A–C – lake, Shanxi (C. chinensis); D–E – lowland marsh, Shenzhen, Guangdong (C. rugosus, C. tripunctatus lateralis and C. sugillatus); F – temporary pond in a valley, Danxiashan Mt., Guangdong (C. tripunctatus lateralis and C. limbatus); G – natural pond, Lankeshan Mt., Zhejiang (C. rugosus and C. brevis); H – terraced fields pools, Lvchun County, Yunnan (C. convexus and C. sugillatus).

Fig. 19. Live specimens of Chinese Cybister. A – C. chinensis Motschulsky, 1854 (mating couple); B – C. lateralimarginalis torquatus (Fischer von Waldheim, 1829); C – C. rugosus (W. S. Macleay, 1825); D – C. tripunctatus lateralis (Fabricius, 1798); E – C. convexus Sharp, 1882; F – C. sugillatus Erichson, 1834.

Fig. 22. Map of distribution of Cybister in China.